This invention relates to the field of burning sulfur-containing fuels and to reducing the production of SOx, NOx, unburned carbon, and mercury therefrom.
Over the past several years, power generation processes and other combustion processes for burning sulfur-containing fuels have been subject to increasingly strict emissions restrictions, particularly for NOx SOx, unburned carbon, and elemental mercury. Sulfur-containing fuels that are popular for power generation but especially problematic for emissions include coal, petcoke and heavy fuel-oil boilers. Current methods of removing SOx from, e.g., coal fired boilers are very expensive. It is anticipated that within a few years, most of those boilers in the U.S. will require de-sulfurization equipment. NOx, unburned carbon, and elemental mercury removal techniques are similarly expensive, complex and difficult to operate. The preferred embodiments of the present invention disclose cost-effective methods to remove SOx, NOx as well as unburned carbon and mercury.
Thus, a problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they produce a level of SOx emission that is unacceptable in view of existing environmental regulations.
Yet another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they produce a level of NOx emission that is unacceptable in view of existing environmental regulations.
Still another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they produce levels of unburned carbon and elemental mercury emissions that are unacceptable in view of existing environmental regulations.
Another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been successively modified to provide adequate combustion characteristics resulting in adequate reduction of NOx formation sufficient to meet environmental guidelines without expensive and complex NOx treatment apparatus.
A further problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been successively modified to provide adequate combustion characteristics resulting in adequate reduction of SOx formation sufficient to meet environmental guidelines without expensive and complex SOx treatment apparatus, such as scrubbers, etc.
Another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been successively modified to provide adequate combustion characteristics resulting in adequate reduction of NOx formation sufficient to meet environmental guidelines without expensive and complex NOx treatment apparatus.
An even further problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been provided with a means for chemically preventing the formation of SOx and concurrently provided with a mechanism to avoid problems associated with slagging or other fouling of the combustion equipment.
Another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been provided with a means for chemically preventing the formation of NOx and concurrently provided with a mechanism to avoid problems associated with slagging or other fouling of the combustion equipment.
For the foregoing reasons, there has been defined a long felt and unsolved need for a process for burning sulfur-containing fuels that facilitates an inexpensive, non-intrusive method for reducing the formation of SOx while at the same time maintaining the operability and safety of the combustion process.